Quick backstory. I build widgets for a living, some big and complex with a lot of parts. I generally get the order for the 6" widgets in batches of 20 so I pick parts from the warehouse for 20 at a time. I like my parts cart organized a really specific way because it allows me to be more efficient. I organize my parts as I take them from the shelves so it doesn't add any significant delays to the time I spend picking parts.
The players in this case are Mary, a shop hand, Jamie, a supervisor, and me.
I got an order for 20 more widgets just as I was finishing the last widget from the last order. So, my carts were empty and I had to get parts for 20 more 6" widgets. Jamie, thinking to speed the process up, delegated this task to Mary. Mary has never built these widgets so she was referring to a book (which we jokingly call "the bible" because it "has all the answers") that shows drawings of the widgets, how they are assembled and what parts they need, along with their part numbers and quantities. For this task, I seldom use the book because I already know. Mary needed the book, which slowed her down a lot as she kept going back to it, rechecking, losing her place, etc. Then she put the parts on the carts "wrong". (by this I mean they weren't wrong, just they weren't how I would do them) and she pulled some parts that we don't actually pull til the very end, when we're ready to use them. When I tried to tell her "We don't pull the flanges out of the crates til the very end so you can just leave them there," she argued, "Well Jamie said to pull the parts in the book for these widgets!" I told her, "I know what Jamie said, but I'm just clarifying for you since you've never done these and might not know. The flanges are listed in the book because they are part of the widget and need to be there; but in the practical process, we don't pull them out of the crates til the end, to make sure nothing's damaged." She completely ignored me and pulled the flanges, thus commandeering 5 parts carts when it should have only taken 2. I also know that Jamie would never tell her to pull those parts; he just has an irksome habit of forgetting that not everyone "just knows" like him and I do, so he sometimes forgets those kinds of details in his instructions.
Then I lost a bunch of time rearranging the parts on my cart, because she had them set up in such a way that I couldn't reach the smaller stuff without knocking over the bigger things. I tried to just use the parts the way they were, but I was losing so much time having to walk around the cart to reach stuff that was in the wrong spot, etc. It was very inefficient so after the first widget was build, I re-organised everything. Plus, I kind of feel like if you want something done as specifically as I like my cart organised, you should really do it yourself.
Now I need to find a diplomatic way to relate what happened, Mary arguing with me (I'm a supervisor as well, just not hers. Jamie is hers.) and how much time I lost re-organising everything. I want to tell him to just let me get my own parts from the warehouse and to just in general stop delegating things to Mary. I get that he's trying to help; he and I are the only ones who build these widgets and right now he is injured, so the whole load is on me. I appreciate for sure that he is trying to make things easier for me, but it's really just costing me time and frustration because she won't listen to me...I suppose she doesn't have to as I'm not her supervisor but I still have seniority (for one) and this is my department and my parts she's getting into now. (for another) . I don't think a reprimand or anything is necessary (though I wouldn't mind if Jamie reminded her that she also has to listen to me) but I just want him to stop delegating this stuff to her. It saves me no time.
I don't want to hurt Jamie's feelings because I know he's really desperate to help me out and he feels badly about his injury, which means he can't do any building right now, but delegating anything to Mary is just a giant waste of time.